This is a note to let you know that I've just added the patch titled
ceph: avoid putting the realm twice when decoding snaps fails
to the 6.0-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
ceph-avoid-putting-the-realm-twice-when-decoding-snaps-fails.patch
and it can be found in the queue-6.0 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 51884d153f7ec85e18d607b2467820a90e0f4359 Mon Sep 17 00:00:00 2001
From: Xiubo Li <xiubli@xxxxxxxxxx>
Date: Wed, 9 Nov 2022 11:00:39 +0800
Subject: ceph: avoid putting the realm twice when decoding snaps fails
From: Xiubo Li <xiubli@xxxxxxxxxx>
commit 51884d153f7ec85e18d607b2467820a90e0f4359 upstream.
When decoding the snaps fails it maybe leaving the 'first_realm'
and 'realm' pointing to the same snaprealm memory. And then it'll
put it twice and could cause random use-after-free, BUG_ON, etc
issues.
Cc: stable@xxxxxxxxxxxxxxx
Link: https://tracker.ceph.com/issues/57686
Signed-off-by: Xiubo Li <xiubli@xxxxxxxxxx>
Reviewed-by: Ilya Dryomov <idryomov@xxxxxxxxx>
Signed-off-by: Ilya Dryomov <idryomov@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/ceph/snap.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
--- a/fs/ceph/snap.c
+++ b/fs/ceph/snap.c
@@ -763,7 +763,7 @@ int ceph_update_snap_trace(struct ceph_m
struct ceph_mds_snap_realm *ri; /* encoded */
__le64 *snaps; /* encoded */
__le64 *prior_parent_snaps; /* encoded */
- struct ceph_snap_realm *realm = NULL;
+ struct ceph_snap_realm *realm;
struct ceph_snap_realm *first_realm = NULL;
struct ceph_snap_realm *realm_to_rebuild = NULL;
int rebuild_snapcs;
@@ -774,6 +774,7 @@ int ceph_update_snap_trace(struct ceph_m
dout("%s deletion=%d\n", __func__, deletion);
more:
+ realm = NULL;
rebuild_snapcs = 0;
ceph_decode_need(&p, e, sizeof(*ri), bad);
ri = p;
Patches currently in stable-queue which might be from xiubli@xxxxxxxxxx are
queue-6.0/ceph-avoid-putting-the-realm-twice-when-decoding-snaps-fails.patch
